Yarn brake



Nov. 18, 1952 K. BUDER 2,618,445

YARN BRAKE Filed NOV. 7, 1950 2 SHEETS-SHEET l l@ @Wm i@ K. BUDER YARNBRAKE Nov. 18, 1952 2 SHEETS-SHEET 2 Filed Nov. 7, 1950 Patented Nov.18, 1952 YARN BRAKE Karl Bilder, Augsburg, Germany, assigner to `osefSailer Maschinenfabrik, Augsburg, Germany Application November 7, 1950,Serial No. 194,467 In Germany November 9, 1949 This invention relates toa yarn brake or yarn tension appliance, more particularly for copcreels, of the type in which the yarn is more or less deflected from itsstraight course by a mechanically or magnetically actuated guidepivotally mounted with respect to a stationary guide.

In a known yarn tension appliance of this type, a spring is arranged insuch a way that it has its minimum tension in case of maximumv deIlection of the yarn from its straight line course, i. e. in a positionWhere it is intended to exert the maximum braking effect upon the yarn,and on the other hand it has its maximum tension when the yarn runs on astraight course and it is intended to produce a minimum braking effector no braking effect at all. Therefore, in order to avoid this highlyundesirable eifect a construction has been proposed in which the carrierof the movable guide engages the passing yarn under action of its ownweight; to this end it has been pivoted at a point disposedeccentrically to its center of gravity of an axis which is parallel tothe direction of course of the yarn. However, since the weight dependingon the kind of material used and the specific gravity thereof is liableto variations and more particularly, in case of the poreclain materialused for this pur pose is diflicult to be determined, a spring has beenadopted as an additional loading means with the result that the abovementioned disadvantage is again present and the intended effect is madeillusory.

It is an object of the present invention to avoid the foregoingdifficulty and to providea yarn brake whose braking effect is properlyadapted to the initial tension of the yarn.

Another object of the invention is to provide means for permitting areliable and easy automatic control of the delecting force exerted uponthe movable guide.

Still another object of the invention is to provide means for permittinga common central control of the deflecting force of a plurality of yarnbrakes or of all yarn brakes of a creel.

With these and further objects in view according to the presentinvention, the spring loading the carrier of the movable guide isarranged in such a way in relation to the pivot of the carrier that itstorque of the carrier remains unchanged or advantageously even growswith increasing deection of the yarn despite the reduction of the springtension, by a proportional or even larger increase of its effectivelever arm. In this manner conditions are provided which can 4 Claims.(Cl. 242-454) be accuratelypredetermined and ensure a satisfactorybraking in accordance with the requirements.

My novel yarn brake moreover renders it unnecessary to arrange the pivoteccentrically with respect to the center of gravity or" the carrier forthe movable guide. Instead, according to a further feature of theinvention the carrier of the movable guide is preferably fulcrumed linsuch a Way as to be in the state of equilibrium as to the gravityforces. To this end, it is preferably pivoted on an axis disposedperpendicularly to the direction of the course of the yarn. In thismanner ail reactions upon the yarn braking lclue to the weight of thecarrier that are incapable of being accurately controlled areeliminated, the braking effect rather being determined exclusively bythe spring force. The pivotal mounting of the carrier of the movableguide on an axis disposed perpendicularly to the direction of course ofthe yarn has the special advantage that in case of the provision of aplurality of deecting points, different positions are obtained withrespect to the pivot axis, so that the deflections at the points whichare more remote from said axis are larger than those at the points whichare disposed closer thereto. Accordingly while in the known arrangementof the pivotal axis parallel to the direction of the course of the yarnall movable guide members cause a uniform deflection, this is not thecase in the appliance according to the present inven-` tion. Thisnon-uniform deflection results in a more gradual and softer change ofthe braking effect. Since in practice it is hardly possible to do With asingle deflecting point, but nearly always a plurality thereof arerequired, it will be understood that for instance in case of sixdeflections in the known construction all of the six deflections actsimultaneously and uniformly. This, primarily during transition from thenonbrake position causes a very sudden growing of the braking eifect,while in my appliance at first only the two extreme deecting pointsbecome effective, then the two intermediate deect ing points and only inthe nal phase all the six deflecting points produce a braking effect,the two extreme ones in the meantime causing a larger deflection andbraking effect than the intermediate ones and the latter again causing alarger deflection than the two innermost deflecting points.

I prefer to mount the carrier of the movable guide in such a way that itis in the state of equilibrium as to gravity forces in two planesdisposed perpendicularly to each other so that a state of balance willexist even in case of a vertical direction of course of the yarn. Tothis end the axis of the pivot is arranged to intersect with the centerof gravity of the carrier of the movable guide. The two guides which aremost adjacent to the pivotal axis are interconnected by a sleeve for thepassage of the yarn on which sleeve the pivot is secured. This sleevealso offers the advantage of facilitating the threading of the yarn inthe setting operation.

According to an important alternative embodiment of the invention thespring may be replaced by an electro-magnet producing the defiectingforce, which magnet can be controlled by adjustment of the excitingcurrent of the electro-magnet. This offers the advantage that the forcecan be changed by simple means which is not possible to a larger extentin case of springs while such adjustment will |be desirable where a widevariety of yarns are to be worked. The electromagnetically operated yarnbrake, moreover, is an improvement in as much as the force can bechanged infinitely and thus can be adapted to the yarn to be actuallyworked with an extreme degree of sensitivity so that even in case ofworking the same type of yarn the most appropriate tension can beaccurately adjusted. Moreover, this oifers the advantage that it ispossible to connect the electromagnets of all yarn brakes of a cop creelto a common means for regulation of the electric current.

Yarn brakes or tension appliances of this general type so far have beenmade of metal or porcelain. The latter has the advantage of awear-resistant surface which is particularly suitable for guiding theyarn. However, porcelain is very fragile and the yarn brake madetherefrom is endangered with each introduction and removal of the cops.The parts of the yarn tension appliance consisting entirely ofporcelain, moreover, cannot be manufactured very accurately. Thisapplies especially for the mounting of the pivot which can be made onlyin a very crude form, whereby the whole yarn tension appliance obtains acrude character.

According t the present invention these disadvantages are alsoeliminated by making the carriers of tlie stationary and of the movableyarn guide of a plastic material in which the eyes forming the threadguide and consisting more particularly of porcelain are interchangeablyinserted, more particularly, cemented. Therefore, in my novel threadbrake the real thread guiding surface is likewise formed of porcelain,but the porcelain eyes are easily interchangeable so that when they areworn out this does not mean that the whole yarn brake has to be junked.The other parts of the yarn brake, however, consist of a syntheticplastic which is practically unbreakable, very light and first of alladapted to be molded into a very accurate shape, for instance, byinjection molding, The parts made of this material can be manufacturedvery cheaply in mass production. The porcelain eyelets can be veryeasily connected thereto by welding or cementing and can be easilyremoved therefrom.

Other and further objects, features and advantages of the invention willbe pointed out hereinafter and appear in the appended claims formingpart of the application.

In the accompanying drawings a now preferred embodiment of the inventionis shown by way of illustration and not by way of limitation.

Fig. 1 is a sectional view, on the line lil-l of Fig. 2,

Fig. 2 is a section on line 2 2 of Fig. 1.

Fig. 3 is a sectional view on line 3-3 of Fig. 4, and

Fig. 4 is a, sectional view on line 4-4 of Fig. 3.

Referring now to the drawings in greater detail it will be seen that thecasing l made of an injection molded synthetic material and adapted tobe mounted on the creel frame comprises two eyelets 3 of porcelaindisposed in such a way that their common axis intersects with the axisof the fulcrum 2 of metal, said eyelets being arranged on the right andon the left 0f said fulcrum, as well as an inlet eye 4 and an outlet eye5, likewise consisting of porcelain, for the yarn 6. Mounted on thepivot 2 is a carrier 8 of plastic material comprising pairs of eyes ofporcelain 9, Ill, and il symmetrically spaced on the right and left ofthe pivot 2. This carrier 8 is in a state of balance in relation to itspivot 2 since the axis of the pivot intersects with the center ofgravity of the carrier Therefore, the pivot 2 is fastened on, or formedintegral with, the sleeve I8.

The carrier 8 is tensioned by a spring 20 engaging the carrier 8 at i9and fastened to the casing I at 2|. By way of alternative, by anelectromagnet i2 comprising terminals I3 and an armature lil operativelyconnected to the carrier il by means of a link member 22 linked to thecarrier 8 at '1. This tension tends to move the carrier il into theposition shown in Fig. l so that the yarn 6 in the condition as shown isdeected from its straight course, the deflection beingl larger at 9 thanat il) and being larger at I0 than at Il. When the tension of the yarn 6rises, it will tend to pull the carrier 8 into its straight line course;in this case the braking effect may be decreased and in fact the brakingeffect is reduced by a reduced extent of the deflections or of the arcof contact between the yarn and its guide points and thereby of thefriction. The torque exerted on the carrier by the spring 20 alsodecreases despite its increased tension because its lever arm inrelation to the pivot 2 in this .case is considerably decreased. Thisalso applies with regard to the link 22 of the electromagnet in itsdotted line position 22.

The arm I3 of synthetic material can be riveted to the casing l at 23 onthe right or left hand side thereof. The terminals 3 of theelectromagnet l2 are connected to an adjustable resistance (not shown)i. e. all magnets of the creel may be connected to a common adjustableresistance whereby the force of attraction of the magnetic armatures canbe infinitely varied by a central control. The articial material selectrically insulating for the electric wires so that no specialinsulation is required. I

.While the invention has been described in detail with respect to a nowpreferred example and embodiment of the invention it will be understoodby those skilled in the art after understanding the invention thatvarious changes and modificat1ons may be made without departing from thespirit and scope of the invention and it is intended, therefore, tocover all such changes and modications in the appended claims.

What is claimed is:

l. In a yarn brake and tensioning device especially for cop creels, acasing, stationary yarn guides carried by the casing, a carrierpivotally mounted intermediate its ends in the casing yarn guides on thecarrier extending into the zone of the stationary guides and capable ofalnement for unrestricted passage of yarn therethrough in a Straightline of movement, means for biasing the carrier and guides thereon andfor moving the guides on the carrier out of alinement with thestationary guides for delecting the yarn from a straight line of travelthrough the guides and for braking and tensioning the yarn, the yarnguides on the carrier being located at opposite sides of the carrierpivot and at equal radial distances from said pivot whereby the carrieris supported in a state of equilibrium, the carrier biasing means beingengaged with the carrier at one side of and adjacent the pivotalmounting of the carrier whereby the tension on the yarn caused by thechange of position of the carrier and guides carried thereby is variedin such manner that the torque exerted by the biasing means on thecarrier remains substantially constant as the tension on the yarndecreases while the deflection of the yarn increases.

2. In a yarn brake and tensioning device, especially for cop creels, acasing, stationary yarn guides carried by the casing, a carrierpivotally mounted intermediate its ends in the casing, yarn guides onthe carrier extending into the zone of the stationary guides and capableof alinement with the stationary guides for unrestricted passage of yarntherethrough in a straight line of movement, a spring connected to thecarrier for biasing the carrier and guides thereon and for moving theguides on the carrier out of alinement with the stationary guides fordeiiecting the yarn from a straight line of travel through the guidesfor braking and tensioning the yarn, the yarn guides on the carrierbeing located at opposite sides of the carrier pivot and at equal radialdistances from said pivot whereby the carrier is supported in a state ofequilibrium, the spring being attached at one end to the casing and atits other end to the carrier adjacent the side of the carrier pivotnearer the opposite end of the casing whereby tension on the yarn causedby the changed position of the carrier and guides carried thereby isvaried in such manner that the torque exerted by the spring on thecarrier remains substantially constant as the tension on the yarndecreases While the deflection of the yarn increases.

3. In a yarn brake and tensioning device, especially in cop creels, acasing, stationary yarn guides carried by the casing, a carrierpivotally mounted intermediate its ends in the casing, yarn guides onthe carrier extending into the zone of the stationary guides and capableof alinernent with the stationary guides for unrestricted passage ofyarn therethrough in a straight line of movement, an electromagnethaving a link connection with the carrier for biasing the carrier andguides thereon and for moving the guides on the carrier out ofalineinent with the stationary guides for deecting the yarn from astraight line of travel through the guides for braking and tensioningthe yarn, the yarn guides on the carrier being located at opposite sidesof the carrier pivot and at equal radial distances from said pivotwhereby the carrier is supported in a state of equilibrium, theelectromagnet being carried by the casing and a link being connected tothe carrier adjacent one side of the carrier pivot whereby the tensionon the yarn caused by the changed position of the carrier and guidecarried thereby is varied in such manner that the tonque exerted by theelectromagnet on the carrier remains substantially constant as thetension on the yarn decreases while the deflection of the yarnincreases.

4. A yarn brake as in claim 1, wherein a sleeve is supported on thecarrier at one side thereof between and in line with the yarn guides onthe carrier, and the two yarn guides adjacent opposite sides of thecarrier pivot being supported in the ends of the sleeve.

KARL BUDER.

REFERENCES CITED The following references are of record in the le ofthis patent:

FOREIGN PATENTS Number Country Date 22,908 Switzerland Nov. 16, 1900528,386 Great Britain Oct. 29, 1940

